1. Field of the Invention
The present invention relates to a printing plate removing/supplying device which removes a predetermined printing plate from plural cassettes in which printing plates are respectively accommodated, and conveys and supplies the predetermined printing plate to a section-to-be-supplied-to, which is a subsequent process.
2. Description of the Related Art
A technique in which, by using a printing plate (e.g., a PS plate, a thermal plate, a photopolymer plate) in which a recording layer (photosensitive layer) is provided on a support, an image is recorded directly by a laser beam or the like onto the photosensitive layer of the printing plate, has come to be developed as a printing plate exposing device. With this technique, it is possible to quickly record an image onto a printing plate.
In an automatic printing plate exposing device using the technique of recording images on printing plates, printing plates are removed one-by-one from a cassette in which a plurality of the printing plates are stacked, and are fed in to an exposure section.
Printing plates are classified into plural types in accordance with their size, photosensitizing method, material, and the like. Generally, a single type of printing plate is accommodated in any given cassette. In a state in which plural cassettes are stacked one above another in plural levels, the cassettes are accommodated within a cassette stocker portion (accommodating portion) and are supported on rails which are fixed to the inner walls of the cassette stocker portion. Refer to, for example, Japanese Patent Application Laid-Open (JP-A) No. 2000-351460.
At the time of refilling and loading in printing plates, side surface covers of the cassette stocker portion are opened to the left and the right, a cassette is pulled out horizontally along the rails of the cassette stocker portion and rails fixed to the side surface covers, and printing plates are loaded into the cassette.
Therefore, when setting the automatic printing plate exposing device, it is necessary to ensure space for the pulling-out of the cassettes (space for opening and closing the side surface covers). A problem arises in that ultimately a large space for placement of the device is needed. For example, in a case in which the size of the largest printing plate is 1160 mm by 940 mm, the space needed for pulling out the cassette is about 1300 mm by 1100 mm.
Further, the cassette which is pulled out to the exterior of the cassette stocker portion is supported on rails which are fixed to the side surface covers. However, the printing plates are heavy. For example, the total weight of 100 of the largest printing plates is 100 kg. The rigidity of the side surface covers and the members supporting the side surface covers (hinges or the like) must be made to be high, which results in the cost of the device increasing.
In addition, because the cassettes are accommodated in plural levels in a state in which one is disposed above another, when the device is set such that the height which makes the printing plate loading work easy is the height of the uppermost cassette, a problem arises in that the workability at the time of loading printing plates into the lower cassettes is poor.